"Alcohol appears to disrupt the healthy balance in the lung," said study lead author Dr. Majid Afshar, of Loyola University Chicago. He is an assistant professor in the division of pulmonary and critical care medicine and department of public health sciences.

Afshar's team analyzed data from more than 12,000 American adults. The researchers found that heavy drinkers (more than one drink a day for women and more than two drinks a day for men) and people who binge-drink at least once a month had less nitric oxide in their exhaled breath than non-drinkers. Binge-drinking is consuming four or more drinks per occasion for women and five or more drinks for men.

Also, the researchers found that the more alcohol heavy drinkers consumed, the lower the level of nitric oxide.

Nitric oxide helps protect the lungs against certain types of harmful bacteria, the researchers explained. The study is the first to find a link between excessive drinking and nitric oxide, according to the researchers.

The findings were published recently in the journal Chest.

In asthma patients, nitric oxide levels in exhaled breath give a good indication of how well their medication is working. Excessive drinking might complicate the results of such tests, the researchers said.

"Lung doctors may need to take this into consideration," Afshar said in a university news release. He added that further research is needed to learn more about the interaction between alcohol and nitric oxide in the airways.